My Costco had Season Brand Boneless/Skinless Sardines in Olive Oil about 8 months ago on sale and then they were out and haven't seen them since. I don't know if they will bring them back at some point but they are the best sardines I've ever had. The cost came out to something around $1.40/can. Since I liked them so much I've bought more off of Amazon but the price is much higher, about $2.20/can.

I bought a case of MW Polar Sardines in Olive Oil from Amazon for $1.87/can but now the price with shipping is up to $2.35/can. The quality is very good, similar to the Season Brand sardines.

Not a fatty fish but I really love these canned MW Polar Kippers (smoked herring), the quality is excellent. I've found the best price on these at Walmart, don't remember exact amount but it was a $1 something and cheaper than anywhere else I looked including Amazon.